Research may hold key to unlocking cause and finding treatment for age-related hearing loss

Age-related hearing loss is among the top three chronic conditions affecting adults 65 years or older, according to the National Center for Health Statistics. Current Creighton University research may hold the key to unlocking a cause and finding a treatment for age-related hearing loss.

Creighton University Professor David Zhi-Zhou He, MD, PhD recently received a $1.9 million R01 grant from National Institute on Deafness and Other Communication Disorders, part of the National Institutes of Health (NIDCD/NIH), to research what causes age-related hearing loss. His research, "Mechanism of biological aging of cochlear hair cells," began Aug. 1 and will continue until July 2023. This is the fourth NIH R01 grant that He has brought to Creighton University since 2003.

He believes the secret to unlocking the cause of age-related hearing loss could be related to the hair cell degeneration in our ears. Much of He's research will focus on inner and outer hair cells, the two types of receptor cells that convert sound into electrical impulses in the auditory nerve. He will compare the changes at the cellular and molecular levels of hair cells between young and aging mice to determine age-related changes in gene expression, ultrastructure and cellular function.

He's research has three goals:

• Identify what causes the sensory receptor hair cells to degenerate.
• Determine why age-related hearing loss occurs from high frequencies to low frequencies.
• Determine why outer hair cells degenerate before inner hair cells.

The research also will look closer at the CLU gene, or Clusterin, known to play a role in degeneration of neurons in the brain, to determine if the gene also plays an important role in hair cell aging.

"Loss of hearing in the elderly also can contribute to social isolation and loss of autonomy, and is associated with anxiety, depression and cognitive decline. Currently, there is no medication available to treat or postpone age-related hearing loss," He says. "We hope to identify genes and pathways that control the aging process in hair cells, especially outer hair cells, which are more subject to aging, noise and ototoxic drugs. Hopefully, the knowledge gained will be useful for developing therapeutic treatment to postpone age-related hearing loss"